Improved chuck



EPHRAIM S. WILLIAMS, OF CAMBRIDGE, MASSACHUSETTS.

Leners Pawn No'. 95,297, dared sepmbr 2s, 1869.

IMPROVED GHUGK The Schedule referred to in these Letters Patent andmaking part of the'sama To all whom it may concern Beit known that I,EPHRAIM S. WILLIAMS, of Cambridge, in the county of Middlesex, and Stateof Massachusetts, have invented certain new and useful Improvements inMandrels, Chucks, Sac.; and I do hereby declare that the following isafull and exact my invention, 1 will proceed to describe its constructionand use.

Drawings.

Figure 1 is a perspective view, showing the mandrel.

Figure 2 is a perspective view, showing a chuck. Y I construct myimproved inandrels, chucks, faceplates, Szc., in the ordinary manner,except in the chuckscrew C of,the mandrel A, fig. 1, I form a groove, ef, and in the female sc'ew of the` face-plate or chuck, H, I form aslot, l m. These slots, e-f and l-m., may extend through all 'of thethreads, as shown, or only through one or two of them, the design of theslots being to clear the thread of any chips, dust, or dirt that may bein them.

The advantages and operation of this device are too obvious to needexplanation.

What I claim as my invention, and desire to secure by LettersPatent ofthe United States, is-

The chuck-screw, when provided with a slot, e f or lm, substantially asdescribed and for the purpose set forth.

EPHRAIM S. WILLIAMS. Vitnesses:

FRANK G. PARKER, A. HUN BERRY.

